Strewing apparatus for sand, gravel and similar material



Feb. 8, 1966 K. E. D. EJNARSSON 3,233,736

GRAVEL AND SIMILAR MATERIAL STREWING APPARATUS FOR SAND,

Filed July 13, 1964 2 Sheets-Sheet 1 F IG] INVENTOR fi A 1 1. Emma $4100 EMA/2550M BYEMLZJW ATTORNEY K. E. D. EJNARSSON 3,233,786

2 Sheets-Sheet 2 INVENTOR BY M ATTORNEY STREWING APPARATUS FOR SAND, GRAVEL AND SIMILAR MATERIAL TIIIIIJQ Feb. 8, 1966 Filed July 13, 1964 United States Patent Ofifice Patented Feb. 8, 1966 3,233,786 STREWING APPARATUS FOR SAND, GRAVEL AND SIMILAR MATERIAL Karl Einar David Ejnarsson, Stragatan 20, Vadstena, Sweden Filed July 13, 1964, Ser. No. 382,295 3 Claims. (Cl. 222-477) This invention refers to a strewing apparatus for sand, gravel and similar material, with road wheels and a funnel-shaped hopper for the material to be strewn, narrowing downwards and ending in a spreader opening or outlet aperture running across the direction of travel and where an eccentric is fitted with its axle parallel to the road wheels axle, and driven by at least one of the road wheels.

With an apparatus of this type it frequently happens that the material to be strewn forms lumps, and in winter time, lumps of frozen strewing material may be large enough and hard enough to prevent an even distribution of the material.

The object of this invention is to provide a strewing apparatus which, in a simple and reliable manner, will overcome this problem.

This is achieved, according to the invention, by the movement of the eccentric being transferred to a movable sieve or screen placed over the outlet aperture. The movement of the screen breaks up the strewing material. This movable screen makes it possible to use sand taken straight from outdoor storage, or gravel pit; the screen prevents larger stones from damaging the machinery, as well as breaking down frozen lumps with considerable effect.

Preferably, according to the invention, the movement from the eccentric should also be transferred to a flexible lip in the outlet aperture. This lip will ensure that the material is evenly dispensed from the aperture.

If the material which passes through the screen is not sufficiently loosened or broken down, an axle, according to the invention, with studs or similar configurations around the circumference, may be fitted between the outlet aperture and the screen in such a manner that it can be driven by at least one of the road wheels.

In a prefered version of the invention, a wall of flexible material would be fitted in the outlet aperture on the opposite side of the above mentioned lip, and fixed, at its upper end, to one side of the sieve or screen, whilst the lip is connected to the opposite side of the sieve or screen in such a manner that the space below the said sieve or screen has two walls of flexible material running down the sides of the feed opening, moving with the sieve or screen.

An example of the invention is explained below in more detail with reference to the drawings.

FIGURE 1 shows a cross section of a strewing apparatus according to the invention.

FIGURE 2 is a section of the same machine cut along the axle.

The apparatus consists of a hopper 1 for the material to be strewn. The hopper 1 is funnel-shaped at rightangles to the direction of travel, and narrows downwards towards an outlet aperture 2. The apparatus is intended for towing behind a lorry or truck in the direction indi cated by the arrow. The lorry should preferably be of the tipping variety to facilitate refilling of the hopper as required. At both ends of the apparatus, road wheels 4 are fitted to an axle in such a way that they may revolve. The outlet aperture 2 is adjustable by means of a movable lever 5, which may be operated through a system of levers by the adjusting lever 6. The lever 5 is connected,

by means of a rubber buffer or rubber profile 7, to an angular rail 8, which controls the size of the opening in the outlet aperture, and which is connected to a flexible sheet 9 made, for example, of rubber, stretching upwards along one side of the funnel-shaped part. With its axle parallel to the axle 3 of the road wheels, an eccentric 11 is fitted in such a way that it may be driven by one of the road wheels by means of a chain 10. The eccentric is connected to a screen 12 by means of an arm 18 and a member 253, in such a manner that the eccentric movement is transferred to the screen on its one side whilst its other side rests on a rubber buffer or rubber profile 13. This side of the funnel-shaped hopper 1 is fitted with a flexible sheet 14 made, for example, of rubber, which extends over a supporting member 15, which is also connected to the eccentric by means of an arm 19 and the member 20 bearing on the eccentric. The supporting member 15 and the flexible sheet 14 stretch out as a lip in the outlet aperture 2. The flexible sheet 14 is fixed at the top only, and hangs loosely down over the end of the eccentric-driven supporting member 15. In this manner, stones with a diameter of up to 30 mm. can be squeezed out when the aperture opening is adjusted to the smallest clearance, thus preventing the space between the screen and the outlet aperture becoming blocked. The combined vibratory movement of the screen 12 and the lip 15 will, in most cases, ensure an even distribution of the material to be strewn. Should it, however, prove necessary an axle 16 can be mounted on the road wheels axle 3, in such a manner that it can be connected to one or both road wheels 4, and which, on the outside, is fitted with studs or similar configurations, not shown in the drawing, for loosening or breaking up the material to be strewn. When the apparatus is disconnected from the traction vehicle, a foot 17 may be released, as indicated in FIGURE 1 with dotted lines, so that the apparatus may be parked in a favourable attitude.

I claim:

1. Apparatus for distributing material, comprising a hopper, road wheels on which the hopper is mounted for travel, the hopper terminating downwardly in an outlet aperture extending transversely to the direction of travel of the hopper, rotatable eccentric means, means for rotating the eccentric means upon movement of the hopper on its road wheels, a sieve mounted for movement above the outlet aperture, a lip of flexible material disposed in the outlet aperture, and means for transmitting movement of said eccentric means both to said sieve and to said lip.

2. Apparatus as claimed in claim 1, said eccentric means being rotatable about an axis parallel to the axis of said road wheels.

3. Apparatus as claimed in claim 1, said means for rotating the eccentric means comprising means drivingly interconnecting the eccentric means and at least one of the road wheels.

References Cited by the Examiner UNITED STATES PATENTS 2,394,778 2/1946 Holloway 222177 2,906,438 9/1959 Carpenter 222-177 3,077,290 2/1963 Rehder 275-177 X FOREIGN PATENTS 103,081 12/1956 Netherlands.

RAPHAEL M. LUPO, Primary Examiner.

CHARLES R. CARTER, Examiner. 

1. APPARATUS FOR DISTRIBUTING MATERIAL, COMPRISING A HOPPER, ROAD WHEELS ON WHICH THE HOPPER IS MOUNTED FOR TRAVEL, THE HOPPER TERMINATING DOWNWARDLY IN AN OUTLET APERTURE EXTENDING TRANSVERSELY TO THE DIRECTION OF TRAVEL OF THE HOPPER, ROTATABLE ECCENTRIC MEANS, MEANS FOR ROTATING THE ECCENTRIC MEANS UPON MOVEMENT OF THE HOPPER ON ITS ROAD WHEELS, A SIEVE MOUNTED FOR MOVEMENT ABOVE THE OUTLET APERTURE, A LIP OF FLEXIBLE MATERIAL DISPOSED IN THE OUTLET APERTURE, AND MEANS FOR TRANSMITTING MOVEMENT OF SAID ECCENTRIC MEANS BOTH TO SAID SIEVE AND TO SAID LIP. 